Operators want to prevent subscribers from accessing illegal content in the following situations:
court-ordered URL takedown
child pornography related content
government-mandated URL takedown list
Operators can use AA to comply with these regulatory requirements, typically driven by government or court order to control the access to specific URLs hosting illegal content. In the context of child protection the operator may be required or incited to provide this filtering.
Local URL-list filtering is applied network-wide to all subscribers. This solution provides a cost-efficient method by storing the list of URLs to be filtered on the system compact flash. Therefore, using the AA-ISA ICAP functionality along with an external server is not necessary.
The ISA-AA local url-list filtering policy provides URL control capability using a list of URLs contained in a file stored on one of the system’s compact flash cards. The router uses the AA capabilities to extract the URL from the subscriber's HTTP request and compares it to the list of URLs contained in this local file. If a match is found, the subscriber flow is redirected to a preconfigured web server landing page typically describing why the access to this resource was denied.